Cougar sightings are "rare," according to the Oregon Department of Fish and Wildlife. But the big cats have been spotted in five metro-area cities in the past month, including two locations in Hillsboro.

Hillsboro's Rood Bridge Park was closed Wednesday morning after three such reports starting Tuesday evening. City spokesman Patrick Preston said it would remain closed until Thursday morning, at which time Parks & Recreation officials will re-evaluate. ODFW has been asked to assist, but the department could not do so immediately, and the rain would have made a search difficult, Preston said.

In late June, Hillsboro's Jackson Bottom Wetlands Preserve was closed twice in a week after "credible" cougar sightings. Though city and state officials never located the animal, one Hillsboro resident told The Oregonian that the animal got within 30 feet of her on a preserve trail, close enough for her to "count the whiskers" on its face.

Reported cougar sightings also came in this month from Happy Valley, West Linn and Oregon City. The state is home to more than 5,000 of the animals, also known as mountain lions, according to ODFW.

Dana Sanchez, a wildlife extension specialist at Oregon State University, said cougars may be moving into the Portland area because of a possible increase in deer and other animals the cats prey upon.

"Cougars are large, mobile predators," Sanchez said. "They generally prey on deer, but where deer and other food becomes available, cougars – especially the younger, dispersing animals – will explore for other opportunities."

She added that cougars are territorial and protective, so younger ones often have to find their own home ranges once they become "sub-adults."

"And quite often, the established adults already have the best places," Sanchez said.

Don Whittaker, of the ODFW wildlife division, said "the area surrounding the Portland-metro area and the suburbs is good cougar habitat."

"Cougar populations are healthy, and the lifestyle choices that make quality of life in the Portland area good also create avenues for animals to come into the cities," he said, referring to the extensive forests and trails that lead directly into urban zones.

But Whittaker cautioned that some of the reported "sightings" might not be cougars at all.

"There's corridors to and from the wild areas, and there's been a lot of attention in the public media that large carnivores have been in the city," he said. "And so people are aware and have been looking for things like that sometimes. Sometimes they're real, sometimes they're not."

The state Fish and Wildlife website has a section devoted to "living with wildlife," which includes a page about cougars. If you encounter one, the guidelines say, do not run, maintain direct eye contact and stand your ground –- and then back away slowly. Cougars often will retreat if given the opportunity, according to the agency.

Sanchez said area residents would do best to familiarize themselves with the guidelines, which include keeping pets indoors at dawn and dusk.

"I think that people do need to start becoming aware that those animals might be in the areas that they're using, especially in the more open, park-like areas," she said.

Another reason mountain lions could be appearing more often, Sanchez said, is increased development.

"Our cities and towns keep expanding," she said. "As we go into those last patches where deer and cougars might be living … we're going to be more likely to potentially see them and encounter them."